A. Components: The swimming pool's recirculation system shall consist of plumbing equipment, hair and lint catcher, filters together with the necessary pipe connections to the pool inlets and outlets, facilities and pipe connections necessary for backwashing filters and facilities and equipment for disinfecting the pool water.
B. Capacity:
1. Hourly: Every swimming pool shall have a recirculating system with an hourly capacity equal to the pool volume divided by eight (8).
2. Turnover: The recirculation system pump shall have sufficient capacity to discharge the volume of water required for an eight (8) hour turnover of the pool against the maximum head in the recirculation system.
C. Pump: The pump used for backwashing filters shall have sufficient capacity to provide a filter backwash rate of at least twelve (12) gallons per minute per square foot of filter area.
D. Hair And Lint Catcher; Strainer: A hair and lint catcher or strainer shall be installed on the suction side of the circulation pump to prevent hair, lint and other extraneous matter from reaching the pump and filters. Hair and lint catchers shall be so designed that they can be easily dismantled for cleaning and inspection and shall be so located as to be easily accessible for cleaning. The design features shall be as follows:
1. Water passes through the strainer from the outside;
2. The strainer is made of noncorrosive material, the width or diameter of strainer openings shall be not more than one-eighth inch (1/8");
3. The area of the strainer openings shall be at least five (5) times the cross sectional area of the inlet pipe to the strainer.
E. Rapid Pressure Filters: Recirculating systems shall contain rapid pressure filters. Sufficient filter area shall be provided to filter the entire contents of the pool in eighteen (18) hours at the rate of not more than three (3) gallons per square foot of filter area per minute. The filter backwashing facilities shall be sufficient to backwash at a rate of twelve (12) gallons per minute per square foot of filter area.
F. Backwash Water And Effluents: All backwash water and effluents shall be discharged to the sewer through an indirect connection. Pressure filters shall be equipped with readily accessible air relief valves, loss of head or pressure gauges on the inlet and outlet pipes and an access head or hold large enough to permit inspection, maintenance and repair work. Sight glasses that can be easily removed for cleaning shall be provided in the effluent line from the filter units.
G. Disinfection: Equipment shall be provided for the disinfection of all pool water. Any disinfection method using materials other than chlorine compounds shall be subject to the approval of the building inspector. Disinfection equipment installed for the use of chlorine compounds shall have sufficient capacity to maintain a minimum free chlorine residual of five-tenths (0.5) parts per million. The disinfection shall be introduced into the recirculation system ahead of the filters.
H. Gaseous Chlorination Systems Prohibited: Gaseous chlorination systems shall not be made use of as a disinfection method for pool water. (1997 Code)